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1.
Blood ; 144(14): 1521-1531, 2024 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-38985835

RESUMO

ABSTRACT: Red blood cells (RBCs) have been hypothesized to support hemostasis by facilitating platelet margination and releasing platelet-activating factors such as adenosine 5'-diphosphate (ADP). Significant knowledge gaps remain regarding how RBCs influence platelet function, especially in (patho)physiologically relevant hemodynamic conditions. Here, we present results showing how RBCs affect platelet function and hemostasis in conditions of anemia, thrombocytopenia, and pancytopenia and how the biochemical and biophysical properties of RBCs regulate platelet function at the blood and vessel wall interface and in the fluid phase under flow conditions. We found that RBCs promoted platelet deposition to collagen under flow conditions in moderate (50 × 103/µL) but not severe (10 × 103/µL) thrombocytopenia in vitro. Reduction in hematocrit by 45% increased bleeding in mice with hemolytic anemia. In contrast, bleeding diathesis was observed in mice with a 90% but not with a 60% reduction in platelet counts. RBC transfusion improved hemostasis by enhancing fibrin clot formation at the site of vascular injury in mice with severe pancytopenia induced by total body irradiation. Altering membrane deformability changed the ability of RBCs to promote shear-induced platelet aggregation. RBC-derived ADP contributed to platelet activation and aggregation in vitro under pathologically high shear stresses, as observed in patients supported by left ventricular assist devices. These findings demonstrate that RBCs support platelet function and hemostasis through multiple mechanisms, both at the blood and vessel wall interface and in the fluidic phase of circulation.


Assuntos
Plaquetas , Eritrócitos , Hemostasia , Animais , Hemostasia/fisiologia , Plaquetas/metabolismo , Eritrócitos/metabolismo , Eritrócitos/citologia , Camundongos , Difosfato de Adenosina/metabolismo , Agregação Plaquetária , Humanos , Camundongos Endogâmicos C57BL , Trombocitopenia/patologia , Trombocitopenia/sangue , Transfusão de Eritrócitos
2.
Brain ; 147(4): 1294-1311, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38289861

RESUMO

Ischaemic stroke causes neuron loss and long-term functional deficits. Unfortunately, effective approaches to preserving neurons and promoting functional recovery remain unavailable. Oligodendrocytes, the myelinating cells in the CNS, are susceptible to oxygen and nutrition deprivation and undergo degeneration after ischaemic stroke. Technically, new oligodendrocytes and myelin can be generated by the differentiation of oligodendrocyte precursor cells (OPCs). However, myelin dynamics and their functional significance after ischaemic stroke remain poorly understood. Here, we report numerous denuded axons accompanied by decreased neuron density in sections from ischaemic stroke lesions in human brain, suggesting that neuron loss correlates with myelin deficits in these lesions. To investigate the longitudinal changes in myelin dynamics after stroke, we labelled and traced pre-existing and newly-formed myelin, respectively, using cell-specific genetic approaches. Our results indicated massive oligodendrocyte death and myelin loss 2 weeks after stroke in the transient middle cerebral artery occlusion (tMCAO) mouse model. In contrast, myelin regeneration remained insufficient 4 and 8 weeks post-stroke. Notably, neuronal loss and functional impairments worsened in aged brains, and new myelin generation was diminished. To analyse the causal relationship between remyelination and neuron survival, we manipulated myelinogenesis by conditional deletion of Olig2 (a positive regulator) or muscarinic receptor 1 (M1R, a negative regulator) in OPCs. Deleting Olig2 inhibited remyelination, reducing neuron survival and functional recovery after tMCAO. Conversely, enhancing remyelination by M1R conditional knockout or treatment with the pro-myelination drug clemastine after tMCAO preserved white matter integrity and neuronal survival, accelerating functional recovery. Together, our findings demonstrate that enhancing myelinogenesis is a promising strategy to preserve neurons and promote functional recovery after ischaemic stroke.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Camundongos , Animais , Humanos , Idoso , Bainha de Mielina/patologia , Isquemia Encefálica/complicações , Isquemia Encefálica/patologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/patologia , Oligodendroglia/patologia , Neurônios , Diferenciação Celular/fisiologia
3.
J Neurosci ; 43(11): 1859-1870, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36725322

RESUMO

Age-related decline in visual functions is a prevalent health problem among elderly people, and no effective therapies are available up-to-date. Axon degeneration and myelin loss in optic nerves (ONs) are age-dependent and become evident in middle-aged (13-18 months) and old (20-22 months) mice of either sex compared with adult mice (3-8 months), accompanied by functional deficits. Oligodendrocyte (OL) turnover is actively going on in adult ONs. However, the longitudinal change and functional significance of OL turnover in aging ONs remain largely unknown. Here, using cell-lineage labeling and tracing, we reported that oligodendrogenesis displayed an age-dependent decrease in aging ONs. To understand whether active OL turnover is required for maintaining axons and visual function, we conditionally deleted the transcription factor Olig2 in the oligodendrocyte precursor cells of young mice. Genetically dampening OL turnover by Olig2 ablation resulted in accelerated axon loss and retinal degeneration, and subsequently impaired ON signal transmission, suggesting that OL turnover is an important mechanism to sustain axon survival and visual function. To test whether enhancing oligodendrogenesis can prevent age-related visual deficits, 12-month-old mice were treated with clemastine, a pro-myelination drug, or induced deletion of the muscarinic receptor 1 in oligodendrocyte precursor cells. The clemastine treatment or muscarinic receptor 1 deletion significantly increased new OL generation in the aged ONs and consequently preserved visual function and retinal integrity. Together, our data indicate that dynamic OL turnover in ONs is required for axon survival and visual function, and enhancing new OL generation represents a potential approach to reversing age-related declines of visual function.SIGNIFICANCE STATEMENT Oligodendrocyte (OL) turnover has been reported in adult optic nerves (ONs), but the longitudinal change and functional significance of OL turnover during aging remain largely unknown. Using cell-lineage tracing and oligodendroglia-specific manipulation, this study reported that OL generation was active in adult ONs and the efficiency decreased in an age-dependent manner. Genetically dampening OL generation by Olig2 ablation resulted in significant axon loss and retinal degeneration, along with delayed visual signal transmission. Conversely, pro-myelination approaches significantly increased new myelin generation in aging ONs, and consequently preserved retinal integrity and visual function. Our findings indicate that promoting OL generation might be a promising strategy to preserve visual function from age-related decline.


Assuntos
Clemastina , Degeneração Retiniana , Camundongos , Animais , Clemastina/farmacologia , Oligodendroglia/fisiologia , Bainha de Mielina/fisiologia , Nervo Óptico , Axônios , Diferenciação Celular/fisiologia
4.
J Cell Mol Med ; 28(13): e18457, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38963011

RESUMO

Allogeneic haematopoietic stem cell transplantation (allo-HSCT) can potentially cure malignant blood disorders and benign conditions such as haemoglobinopathies and immunologic diseases. However, allo-HSCT is associated with significant complications. The most common and debilitating among them is graft-versus-host disease (GVHD). In GVHD, donor-derived T cells mount an alloimmune response against the recipient. The alloimmune response involves several steps, including recognition of recipient antigens, activation and proliferation of T cells in secondary lymphoid organs, and homing into GVHD-targeted organs. Adhesion molecules on T cells and endothelial cells mediate homing of T cells into lymphoid and non-lymphoid tissues. In this study, we showed that Von Willebrand factor (VWF), an adhesion molecule secreted by activated endothelial cells, plays an important role in mouse models of GVHD. We investigated the effect of the VWF-cleaving protease ADAMTS13 on GVHD. We found that ADAMTS13 reduced the severity of GVHD after bone marrow transplantation from C57BL6 donor to BALB/C recipient mice. A recombinant VWF-A2 domain peptide also reduced GVHD in mice. We showed that ADAMTS13 and recombinant VWF-A2 reduced the binding of T cells to endothelial cells and VWF in vitro, and reduced the number of T cells in lymph nodes, Peyer's patches and GVHD-targeted organs in vivo. We identified LFA-1 (αLß2) as the binding site of VWF on T cells. Our results showed that blocking T-cell homing by ADAMTS13 or VWF-A2 peptide reduced the severity of the GVHD after allo-HSCT, a potentially novel method for treating and preventing GVHD.


Assuntos
Proteína ADAMTS13 , Doença Enxerto-Hospedeiro , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Linfócitos T , Fator de von Willebrand , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/imunologia , Animais , Proteína ADAMTS13/metabolismo , Camundongos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Fator de von Willebrand/metabolismo , Humanos , Transplante Homólogo , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Modelos Animais de Doenças , Transplante de Medula Óssea , Células Endoteliais/metabolismo
5.
Inorg Chem ; 63(14): 6546-6554, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38535616

RESUMO

Znln2S4 has great prospects for photocatalytic water splitting to hydrogen by visible light. Herein, a novel Znln2S4-In-MOF (ZnInMS4) photocatalyst is elaborately synthesized by in situ method with In-MOF as the template and In3+ as the source. ZnInMS4 overcomes the fast interface charge recombination and a sluggish charge lifetime via the formed heterojunctions. Photoelectrochemical measurements reveal that the charge-transfer kinetics is enhanced since In-MOF is introduced to act as a reliable charge-transport channel. ZnInMS4 exhibits outstanding cocatalyst-free H2 evolution rate of 70 µmol h-1 under irradiation (λ > 420 nm), which is 3.2-fold higher than that of Znln2S4. In addition, the ZnInMS4 photocatalyst shows good stability in the 16 h continuous reaction. This work illustrates the feasibility of the MOF precursor instead of inorganic salts to directly synthesize photocatalysts with high performance.

6.
BMC Cardiovasc Disord ; 24(1): 191, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570824

RESUMO

AIM: To examine the prognostic value of superoxide dismutase (SOD) activity for monitoring reduced left ventricular ejection fraction(LVEF)in the patients with type 2 diabetes and acute coronary syndrome (ACS). METHODS: The population of this cross-sectional study included 2377 inpatients with type 2 diabetes who had an ACS admitted to the Shandong Provincial Hospital Affiliated to Shandong First Medical University from January 2016 to January 2021. RESULTS: Diabetic patients with ACS were divided into 2 subgroups based on LVEF. The mean SOD activity was significantly lower in patients with an LVEF ≤ 45% than in those with an LVEF > 45% (149.1 (146.4, 151.9) versus 161.9 (160.8, 163.0)). Using ROC statistic, a cut-off value of 148.8 U/ml indicated an LVEF ≤ 45% with a sensitivity of 51.6% and a specificity of 73.7%. SODs activity were found to be correlated with the levels of NT-proBNP, hs-cTnT, the inflammatory marker CRP and fibrinogen. Despite taking the lowest quartile as a reference (OR 0.368, 95% CI 0.493-0.825, P = 0.001) or examining 1 normalized unit increase (OR 0.651, 95% CI 0.482-0.880, P = 0.005), SOD activity was found to be a stronger predictor of reduced LVEF than CRP and fibrinogen, independent of confounding factors. CONCLUSIONS: Our cross-sectional study suggests that SOD activity might be a valuable and easily accessible tool for assessing and monitoring reduced LVEF in the diabetic patients with ACS.


Assuntos
Síndrome Coronariana Aguda , Diabetes Mellitus Tipo 2 , Disfunção Ventricular Esquerda , Humanos , Síndrome Coronariana Aguda/diagnóstico , Volume Sistólico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Biomarcadores , Estudos Transversais , Função Ventricular Esquerda , Disfunção Ventricular Esquerda/epidemiologia , Prognóstico , Superóxido Dismutase , Fibrinogênio
7.
Blood ; 138(25): 2714-2726, 2021 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-34610086

RESUMO

Severe traumatic brain injury (TBI) often causes an acute systemic hypercoagulable state that rapidly develops into consumptive coagulopathy. We have recently demonstrated that TBI-induced coagulopathy (TBI-IC) is initiated and disseminated by brain-derived extracellular vesicles (BDEVs) and propagated by extracellular vesicles (EVs) from endothelial cells and platelets. Here, we present results from a study designed to test the hypothesis that anticoagulation targeting anionic phospholipid-expressing EVs prevents TBI-IC and improves the outcomes of mice subjected to severe TBI. We evaluated the effects of a fusion protein (ANV-6L15) for improving the outcomes of TBI in mouse models combined with in vitro experiments. ANV-6L15 combines the phosphatidylserine (PS)-binding annexin V (ANV) with a peptide anticoagulant modified to preferentially target extrinsic coagulation. We found that ANV-6L15 reduced intracranial hematoma by 70.2%, improved neurological function, and reduced death by 56.8% in mice subjected to fluid percussion injury at 1.9 atm. It protected the TBI mice by preventing vascular leakage, tissue edema, and the TBI-induced hypercoagulable state. We further showed that the extrinsic tenase complex was formed on the surfaces of circulating EVs, with the highest level found on BDEVs. The phospholipidomic analysis detected the highest levels of PS on BDEVs, as compared with EVs from endothelial cells and platelets (79.1, 15.2, and 3.5 nM/mg of protein, respectively). These findings demonstrate that TBI-IC results from a trauma-induced hypercoagulable state and may be treated by anticoagulation targeting on the anionic phospholipid-expressing membrane of EVs from the brain and other cells.


Assuntos
Anexina A5/uso terapêutico , Anticoagulantes/uso terapêutico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Vesículas Extracelulares/efeitos dos fármacos , Fosfolipídeos/metabolismo , Proteínas Recombinantes de Fusão/uso terapêutico , Trombofilia/tratamento farmacológico , Animais , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas Traumáticas/patologia , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/patologia , Masculino , Camundongos Endogâmicos C57BL , Trombofilia/etiologia , Trombofilia/metabolismo , Trombofilia/patologia
8.
Blood ; 137(4): 544-555, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33507292

RESUMO

Traumatic brain injury-induced coagulopathy (TBI-IC) causes life-threatening secondary intracranial bleeding. Its pathogenesis differs mechanistically from that of coagulopathy arising from extracranial injuries and hemorrhagic shock, but it remains poorly understood. We report results of a study designed to test the hypothesis that von Willebrand factor (VWF) released during acute TBI is intrinsically hyperadhesive because its platelet-binding A1-domain is exposed and contributes to TBI-induced vascular leakage and consumptive coagulopathy. This hyperadhesive VWF can be selectively blocked by a VWF A2-domain protein to prevent TBI-IC and to improve neurological function with a minimal risk of bleeding. We demonstrated that A2 given through intraperitoneal injection or IV infusion reduced TBI-induced death by >50% and significantly improved the neurological function of C57BL/6J male mice subjected to severe lateral fluid percussion injury. A2 protected the endothelium from extracellular vesicle-induced injury, reducing TBI-induced platelet activation and microvesiculation, and preventing a TBI-induced hypercoagulable state. A2 achieved this therapeutic efficacy by specifically blocking the A1 domain exposed on the hyperadhesive VWF released during acute TBI. These results suggest that VWF plays a causal role in the development of TBI-IC and is a therapeutic target for this life-threatening complication of TBI.


Assuntos
Lesões Encefálicas Traumáticas/tratamento farmacológico , Fragmentos de Peptídeos/farmacologia , Fator de von Willebrand/antagonistas & inibidores , Reação de Fase Aguda , Animais , Plaquetas/metabolismo , Lesões Encefálicas Traumáticas/complicações , Síndrome de Vazamento Capilar/etiologia , Síndrome de Vazamento Capilar/prevenção & controle , Estudos de Casos e Controles , Hemorragia Cerebral/etiologia , Hemorragia Cerebral/prevenção & controle , Circulação Cerebrovascular , Coagulação Intravascular Disseminada/etiologia , Coagulação Intravascular Disseminada/prevenção & controle , Endotélio Vascular/efeitos dos fármacos , Vesículas Extracelulares , Humanos , Infusões Intravenosas , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/uso terapêutico , Ativação Plaquetária/efeitos dos fármacos , Conformação Proteica , Domínios Proteicos/efeitos dos fármacos , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes de Fusão/uso terapêutico , Fator de von Willebrand/química , Fator de von Willebrand/fisiologia , Fator de von Willebrand/uso terapêutico
9.
Cell Commun Signal ; 21(1): 211, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37596642

RESUMO

Traumatic brain injury (TBI) is a leading cause of injury-related disability and death around the world, but the clinical stratification, diagnosis, and treatment of complex TBI are limited. Due to their unique properties, extracellular vesicles (EVs) are emerging candidates for being biomarkers of traumatic brain injury as well as serving as potential therapeutic targets. However, the effects of different extracellular vesicle subtypes on the pathophysiology of traumatic brain injury are very different, or potentially even opposite. Before extracellular vesicles can be used as targets for TBI therapy, it is necessary to classify different extracellular vesicle subtypes according to their functions to clarify different strategies for EV-based TBI therapy. The purpose of this review is to discuss contradictory effects of different EV subtypes on TBI, and to propose treatment ideas based on different EV subtypes to maximize their benefits for the recovery of TBI patients. Video Abstract.


Assuntos
Lesões Encefálicas Traumáticas , Vesículas Extracelulares , Humanos , Lesões Encefálicas Traumáticas/terapia
10.
Circ Res ; 128(1): 62-75, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33070717

RESUMO

RATIONALE: Hemorrhagic complications represent a major limitation of intravenous thrombolysis using tPA (tissue-type plasminogen activator) in patients with ischemic stroke. The expression of tPA receptors on immune cells raises the question of what effects tPA exerts on these cells and whether these effects contribute to thrombolysis-related hemorrhagic transformation. OBJECTIVE: We aim to determine the impact of tPA on immune cells and investigate the association between observed immune alteration with hemorrhagic transformation in ischemic stroke patients and in a rat model of embolic stroke. METHODS AND RESULTS: Paired blood samples were collected before and 1 hour after tPA infusion from 71 patients with ischemic stroke. Control blood samples were collected from 27 ischemic stroke patients without tPA treatment. A rat embolic middle cerebral artery occlusion model was adopted to investigate the underlying mechanisms of hemorrhagic transformation. We report that tPA induces a swift surge of circulating neutrophils and T cells with profoundly altered molecular features in ischemic stroke patients and a rat model of focal embolic stroke. tPA exacerbates endothelial injury, increases adhesion and migration of neutrophils and T cells, which are associated with brain hemorrhage in rats subjected to embolic stroke. Genetic ablation of annexin A2 in neutrophils and T cells diminishes the effect of tPA on these cells. Decoupling the interaction between mobilized neutrophils/T cells and the neurovascular unit, achieved via a S1PR (sphingosine-1-phosphate receptor) 1 modulator RP101075 and a CCL2 (C-C motif chemokine ligand 2) synthesis inhibitor bindarit, which block lymphocyte egress and myeloid cell recruitment, respectively, attenuates hemorrhagic transformation and improves neurological function after tPA thrombolysis. CONCLUSIONS: Our findings suggest that immune invasion of the neurovascular unit represents a previously unrecognized mechanism underlying tPA-mediated brain hemorrhage, which can be overcome by precise immune modulation during thrombolytic therapy.


Assuntos
AVC Embólico/tratamento farmacológico , Fibrinolíticos/toxicidade , Infarto da Artéria Cerebral Média/tratamento farmacológico , Hemorragias Intracranianas/induzido quimicamente , AVC Isquêmico/tratamento farmacológico , Neutrófilos/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/toxicidade , Animais , Anexina A2/metabolismo , Linhagem Celular , Quimiocina CCL2/metabolismo , Quimiotaxia de Leucócito/efeitos dos fármacos , Modelos Animais de Doenças , AVC Embólico/sangue , AVC Embólico/imunologia , Feminino , Fibrinolíticos/administração & dosagem , Humanos , Infarto da Artéria Cerebral Média/sangue , Infarto da Artéria Cerebral Média/imunologia , Infusões Intravenosas , Hemorragias Intracranianas/sangue , Hemorragias Intracranianas/imunologia , AVC Isquêmico/sangue , AVC Isquêmico/imunologia , Masculino , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Ratos Wistar , Receptores de Esfingosina-1-Fosfato/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Ativador de Plasminogênio Tecidual/administração & dosagem
11.
Pharmacol Res ; 192: 106791, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37156450

RESUMO

Endothelial dysfunction is a key proponent of pathophysiological process of traumatic brain injury (TBI). We previously demonstrated that extracellular vesicles (EVs) released from injured brains led to endothelial barrier disruption and vascular leakage. However, the molecular mechanisms of this EV-induced endothelial dysfunction (endotheliopathy) remain unclear. Here, we enriched plasma EVs from TBI patients (TEVs), and detected high mobility group box 1 (HMGB1) exposure to 50.33 ± 10.17% of TEVs and the number of HMGB1+TEVs correlated with injury severity. We then investigated for the first time the impact of TEVs on endothelial function using adoptive transfer models. We found that TEVs induced dysfunction of cultured human umbilical vein endothelial cells and mediated endothelial dysfunction in both normal and TBI mice, which were propagated through the HMGB1-activated receptor for advanced glycation end products (RAGE)/Cathepsin B signaling, and the resultant NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome activation and canonical caspase-1/gasdermin D (GSDMD)-dependent pyroptosis. Finally, von Willebrand factor (VWF) was detected on the surface of 77.01 ± 7.51% of HMGB1+TEVs. The TEV-mediated endotheliopathy was reversed by a polyclonal VWF antibody, indicating that VWF might serve a coupling factor that tethered TEVs to ECs, thus facilitating HMGB1-induced endotheliopathy. These results suggest that circulating EVs isolated from patients with TBI alone are sufficient to induce endothelial dysfunction and contribute to secondary brain injury that are dependent on immunologically active HMGB1 exposed on their surface. This finding provided new insight for the development of potential therapeutic targets and diagnostic biomarkers for TBI.


Assuntos
Lesões Encefálicas Traumáticas , Vesículas Extracelulares , Proteína HMGB1 , Doenças Vasculares , Humanos , Camundongos , Animais , Fator de von Willebrand , Lesões Encefálicas Traumáticas/complicações , Células Endoteliais da Veia Umbilical Humana
12.
Molecules ; 28(12)2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37375399

RESUMO

Imidazole-based compounds are a series of heterocyclic compounds that exhibit a wide range of biological and pharmaceutical activities. However, those extant syntheses using conventional protocols can be time-costly, require harsh conditions, and result in low yields. As a novel and green technique, sonochemistry has emerged as a promising method for organic synthesis with several advantages over conventional methods, including enhancing reaction rates, improving yields, and reducing the use of hazardous solvents. Contemporarily, a growing body of ultrasound-assisted reactions have been applied in the preparation of imidazole derivatives, which demonstrated greater benefits and provided a new strategy. Herein, we introduce the brief history of sonochemistry and focus on the discussion of the multifarious approaches for the synthesis of imidazole-based compounds under ultrasonic irradiation and its advantages in comparison with conventional protocols, including typical name-reactions and various sorts of catalysts in those reactions.

13.
J Transl Med ; 20(1): 374, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-35982495

RESUMO

BACKGROUND: The role of trimethylamine-N-oxide (TMAO) in the development of diabetes remains controversial, and prospective data are few. We aimed to investigate the association between serum TMAO and incident type 2 diabetes in middle-aged and older adults. METHODS: This study was based on the Guangzhou Nutrition and Health Study (GNHS), a community-based prospective cohort study in China. A total of 2088 diabetes-free participants aged 40-75 years were included from 2008 to 2010. Incident type 2 diabetes was ascertained during follow-up visits. Baseline serum TMAO was measured by high-performance liquid chromatography with online electrospray ionization tandem mass spectrometry. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) for diabetes across tertiles of serum TMAO were calculated using Cox proportional hazard models. Prospective associations of serum TMAO with changes in glycemic traits (fasting glucose, HbA1c, insulin, HOMA-IR) over time were estimated using linear mixed-effects models (LMEMs). RESULTS: We ascertained 254 incident type 2 diabetes cases during a median follow-up of 8.9 years. The median (interquartile range) of serum TMAO was 1.54 (0.86-2.91) µmol/L. From the first to the third tertile of serum TMAO, the multivariable-adjusted HRs for diabetes were 1.00 (reference), 1.17 (95% CI: 0.84-1.61), and 1.42 (95% CI: 1.03-1.96) (P-trend = 0.031). LMEMs showed that the estimated yearly change in fasting glucose was 0.011 (0.001-0.022) mmol/L/y in the highest tertile of serum TMAO, compared with the lowest tertile (P-interaction = 0.044). Serum TMAO was not associated with longitudinal changes in HbA1c, insulin or HOMA-IR. CONCLUSIONS: Our findings suggested that higher serum TMAO was associated with a higher risk of type 2 diabetes and an increase in fasting glucose among middle-aged and older Chinese adults. TRIAL REGISTRATION: NCT03179657. https://clinicaltrials.gov/ct2/show/NCT03179657?term=NCT03179657&draw=2&rank=1.


Assuntos
Diabetes Mellitus Tipo 2 , Idoso , Glicemia , Diabetes Mellitus Tipo 2/epidemiologia , Hemoglobinas Glicadas , Humanos , Insulina , Metilaminas , Pessoa de Meia-Idade , Óxidos , Estudos Prospectivos , Fatores de Risco
14.
World J Surg Oncol ; 20(1): 346, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36258212

RESUMO

BACKGROUND: The prognosis of hepatocellular carcinoma (HCC) varies considerably among patients with the same disease stage and characteristics, and only about two thirds show high levels of α-fetoprotein (AFP), a common prognostic indicator for HCC. Here, we assessed whether the combination of presurgical serum levels of AFP and carbohydrate antigen 19-9 (CA19-9) can predict the prognosis of HCC patients after hepatectomy. METHODS: The clinicopathological characteristics and post-hepatectomy outcomes of 711 HCC patients were retrospectively reviewed. The patients were classified into three groups based on whether their preoperative serum levels of both AFP and CA19-9 were higher than the respective cut-offs of 400 ng/ml and 37 U/ml [double positive (DP)], the level of only one marker was higher than the cut-off [single positive (SP)], or neither level was higher than the cut-off [negative (N)]. The overall survival (OS) and recurrence-free survival (RFS) rates were estimated using Kaplan-Meier curves. Univariate and multivariate survival analyses were performed to identify the clinicopathological factors significantly associated with HCC prognosis. RESULTS: The 1-year, 3-year, and 5-year RFS and OS rates in the N group were significantly higher than those in the SP group, while the DP group showed the lowest rates. Multivariate Cox regression analysis showed that large tumor size (> 5 cm), multiple tumors (≥ 2), incomplete tumor capsule, positive microvascular invasion, Barcelona Clinic Liver Cancer C stage, and CA19-9 level > 37 U/mL were independent risk factors for RFS and OS in HCC patients. Moreover, aspartate aminotransferase levels > 40 U/L proved to be an independent prognostic factor for OS. CONCLUSION: The combination of serum AFP and CA19-9 levels may be a useful prognostic marker for HCC patients after hepatectomy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , alfa-Fetoproteínas/análise , Hepatectomia , Antígeno CA-19-9 , Prognóstico , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Aspartato Aminotransferases , Carboidratos
15.
Int J Mol Sci ; 23(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36430772

RESUMO

In recent studies, phase junctions constructed as photocatalysts have been found to possess great prospects for organic degradation with visible light. In this study, we designed an elaborate rhombohedral corundum/cubic In2O3 phase junction (named MIO) combined with polymeric carbon nitride (PCN) via an in situ calcination method. The performance of the MIO/PCN composites was measured by photodegradation of Rhodamine B under LED light (λ = 420 nm) irradiation. The excellent performance of MIO/PCN could be attributed to the intimate interface contact between MIO and PCN, which provides a reliable charge transmission channel, thereby improving the separation efficiency of charge carriers. Photocatalytic degradation experiments with different quenchers were also executed. The results suggest that the superoxide anion radicals (O2-) and hydroxyl radicals (·OH) played the main roles in the reaction, as opposed to the other scavengers. Moreover, the stability of the MIO/PCN composites was particularly good in the four cycling photocatalytic reactions. This work illustrates that MOF-modified materials have great potential for solving environmental pollution without creating secondary pollution.


Assuntos
Poluentes Ambientais , Catálise , Fotólise , Polímeros
16.
Curr Opin Hematol ; 28(5): 323-330, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34267080

RESUMO

PURPOSE OF REVIEW: Preeclampsia is a common complication of pregnancy and contributes significantly to maternal and fetal morbidity and mortality. A protective hypercoagulable state is often developed during late pregnancy and can evolve into a prothrombotic state in patients with preeclampsia. The underlying mechanism of this prothrombotic transition remains poorly understood. We discuss recent progress in understanding the pathophysiology of preeclampsia and associated prothrombotic state. RECENT FINDINGS: The hypercoagulable state developed during pregnancy is initiated by placental factors and progresses into the prothrombotic state in preeclampsia when the placenta is subjected ischemic and oxidative injuries. The cause of the preeclampsia-induced prothrombotic state is multifactorial, involving not only placental factors but also maternal conditions, which include genetic predisposition, preexisting medical conditions, and conditions acquired during pregnancy. Endotheliopathy is the primary pathology of preeclampsia and contributes to the prothrombotic state by inducing the dysregulation of coagulation, platelets, and adhesive ligands. SUMMARY: Patients with preeclampsia often develop a severe prothrombotic state that predisposes them to life-threatening thrombosis and thromboembolism during and after pregnancy. Early recognition and treatment of this prothrombotic state can improve maternal and infant outcomes of preeclampsia patients.


Assuntos
Predisposição Genética para Doença , Pré-Eclâmpsia , Trombose , Plaquetas/metabolismo , Feminino , Humanos , Placenta/metabolismo , Adesividade Plaquetária , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/genética , Gravidez , Proteínas da Gravidez/sangue , Proteínas da Gravidez/genética , Trombose/sangue , Trombose/genética
17.
Langmuir ; 37(12): 3662-3671, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33739116

RESUMO

By utilizing scanning tunneling microscopy (STM), the self-assembled nanostructures of three characteristic aldehydes have been examined at the solution-solid interface. By introducing the active reactant 5-aminoisophthalic acid (5-AIPA), we succeeded in changing the self-assembled molecular structures through the condensation reaction and obtained the information on structural transformation in real time. The corresponding carboxyl conjugated derivatives were formed in situ and developed into the closely packed and ordered molecular architectures via hydrogen bonds at the solution-solid surface. The relevant simulations have been utilized to interpret the mechanisms of forming the nanostructures. The corresponding theoretical calculation is used to explain the reaction mechanism. Compared with the traditional ways, the on-surface condensation reaction in situ could not only provide a more convenient method for regulating the self-assembled architectures but also offer a promising strategy for building functional nanostructures and devices.

18.
Lasers Med Sci ; 36(8): 1619-1623, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33389306

RESUMO

This study is to determine the role of the fractional CO2 laser in topical drug delivery and the impact of local immune responses. Experimental rabbit nails were treated with fractionated CO2 laser at varied fluencies of 20 mJ, 25 mJ, and 30 mJ and half of which were coated with rhodamine B (RhB). Histological examination was performed by hematoxylin and eosin staining; the penetration of RhB was assessed by the use of confocal laser scanning microscopy; and the expressions of IFN-γ and IL-4 mRNA in situ were detected by means of qPCR at 12 h, 24 h, 3 days, and 7 days post-laser irritation. The fractional CO2 laser could generate microscopic treatment zones in nail plates, and the depths of these micropores as well as the permeation of RhB in nails increased significantly in an energy-dependent manner. Importantly, the laser irritation led an upregulation of local IFN-γ mRNA expression accompanied by a downregulation of IL-4 mRNA expression. The ultrapulsed ablative fractionated CO2 laser may assist topical drug delivery, and may drive stronger local Th1 responses due to an imbalance of IFN-γ/IL-4 expressions, suggesting that the combination of ablative fractionated CO2 laser with topical agents would be an effective option for the treatment of onychomycosis.


Assuntos
Lasers de Gás , Administração Tópica , Animais , Antifúngicos/uso terapêutico , Dióxido de Carbono , Citocinas/genética , Lasers de Gás/uso terapêutico , Unhas , Coelhos , Rodaminas
19.
BMC Surg ; 21(1): 76, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33563248

RESUMO

BACKGROUND: Angular pregnancy is characterized as implant medial to the uterotubal junction in lateral angular of uterine. It was a rare obstetric complication with severe complications like uterine rupture and retained placenta. CASE PRESENTATION: We report a case of 2 incomplete aborted angular pregnancy that was diagnosed and treated with hysteroscopy. In this case, both of patient were performed operative hysteroscopy for incomplete abortion, and with the assistance of hysteroscopy, the angular pregnancy was detected. CONCLUSIONS: Hysteroscopy can more intuitively display the conditions inside the uterine cavity, reduce the intraoperative and postoperative complications, and shorten the hospitalization time of patients. During hysteroscopy, angular pregnancy can be visualized in the upper lateral side of the uterine cavity. Based on the investigation results of clinical cases, this is the first case report of hysteroscopy in the treatment of incomplete aborted angular pregnancy.


Assuntos
Aborto Incompleto/cirurgia , Histeroscopia , Gravidez Angular/cirurgia , Útero/diagnóstico por imagem , Aborto Incompleto/diagnóstico por imagem , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Gravidez , Gravidez Angular/diagnóstico por imagem , Resultado do Tratamento , Útero/cirurgia
20.
Angew Chem Int Ed Engl ; 60(51): 26762-26768, 2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34617655

RESUMO

We disclose that the carbonates of 4-hydroxy-2-cyclopentenones can form π-allylpalladium-based 1,2-carbodipoles, which isomerize to interesting η2 -Pd0 -cyclopentadienone complexes. Compared with the labile parent cyclopentadienone, the HOMO energy of the related η2 -complex was significantly raised via the back-bonding of Pd0 as a π-Lewis base, rendering the uncoordinated C=C bond an electron-richer dienophile in inverse-electron-demand aza-Diels-Alder-type reactions with diverse 1-azadienes. The vinylogous (aza)Morita-Baylis-Hillman or cross Rauhut-Currier addition to (imine)carbonyls or activated alkenes, respectively, was also realized to afford chiral [4+2] or [2+2] cycloadducts, respectively, after trapping the re-generated π-allylpalladium species. New C1 -symmetric ligands from simple chiral sources were developed, exhibiting high stereoselectivity even with racemic substrates via an unusual dynamic kinetic resolution process. Besides, tropone could be similarly activated by a Pd0 complex.

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